14.  Is it okay to use water from the hot water tap for drinking, cooking, or making baby formula?

Hot water generally comes from a hot water heater that may contain impurities that should not be ingested. Some of these impurities might be metals from household plumbing that are concentrated in the heating process. Additionally, these impurities from the household plumbing dissolve more rapidly in hot water than cold water causing the amount of impurities to be higher in hot water.

As little as 0.5 parts per million hydrogen sulfide is detectable by taste in drinking water. Occasionally an odor is present in the hot water only. This condition is usually caused by a chemical reaction which takes place within the water heater. When hot water containing sulfate salts comes into contact with the magnesium sacrificial anode, which is a normal part of most water heaters, a reaction occurs, converting some of the sulfate to hydrogen sulfide. Since the magnesium anode rod is removable, in many cases, removal of the rod is a remedy for the problem. Many people remove the rod entirely. Remember though, the anode is used in a water heater to reduce corrosion in the heater tank and its removal may invalidate the warranty.

In some cases, hydrogen sulfide will occur only in the hot water as a result of a chemical reaction in the water heater itself. Most water heaters contain a corrosion protection device known as a “sacrificial anode.” When dissolved sulfate compounds come in contact with the anode, the resulting chemical reaction converts the sulfates into hydrogen sulfide. Removal of the sacrificial anode will generally eliminate the problem. However, this may void the warranty on the water heater.

The most noticeable effect of hydrogen sulfide is the “rotten egg” odor and sulfur taste it gives to water. The odor and taste of hydrogen sulfide can be detected at levels as low as two-hundreths of a milligram per liter. At the levels normally occurring in drinking water, hydrogen sulfide is not considered a health hazard.

Lead
The primary cause of lead in drinking water is the corrosion of home plumbing materials containing lead. This includes lead solder and flux used to join copper pipes, lead pipes and service connections, and lead alloy pipes.

A soft, acidic water will more readily dissolve lead. The concentration of lead in water will increase with the length of time the water stands in the pipes.

Houses less than five years old are more likely to have elevated lead in the drinking water. With time, most plumbing will develop a protective mineral coating inside the pipes which insulates them from the corrosive action of the water. During the first five years, the plumbing has not had time to develop this protective coating and is more subject to corrosion by the water.

EFFECTS:
Lead is toxic to the human body. It can cause damage to the brain, nervous system, kidneys, and red blood cells. Pregnant women, fetuses, infants, and young children are at the greatest risk of lead poisoning, even if exposed to lead for only a short time. Infants, who consume most of their food in liquid form (baby formula), can receive very large doses of lead through drinking water.

Growing children absorb lead more rapidly than adults. Low levels of lead can have much larger impact on their small bodies than on an adult. Overexposure to lead during this stage of life can permanently stunt their growth.

TREATMENT:
1. Immediate Steps: Do not drink or cook with water that has been in contact with the plumbing for longer than six hours (such as overnight or during a work day). Before using, flush the faucet by letting it run until the water feels cooler. Normally, two to three minutes of flushing will be sufficient to remove the metal-containing water from the pipes.

Never use hot water from the tap to cook with. Hot water is more corrosive than cold water and may contain higher levels of lead. Especially do not use hot water from the tap for making infant formula.

Zinc
The principal cause of zinc in drinking water is the corrosion of galvanized metal. When galvanized metal is exposed to an acidic water, zinc is dissolved from the exposed surface, along with iron and trace amounts of lead and cadmium. The concentration of zinc in the water will be highest after the water has been in contact with the metal for long periods of time.

How should I fill my fish aquarium?  First, allow at least 1 gallon of water to run from the tap before using the water to fill the aquarium.  This will flush any copper or zinc from copper or galvanized piping in your home; tropical fish are very sensitive to small amounts of copper or zinc in their water. 

Q: Drinking water often looks cloudy when first taken from a faucet and then it clears up. Why is that?

A: The cloudy water is caused by tiny air bubbles in the water similar to the gas bubbles in beer and carbonated soft drinks. After a while, the bubbles rise to the top and are gone. This type of cloudiness occurs more often in the winter, when the drinking water is cold.

c. Drinking water pipes- in the street, leading to your home, or in your home-may be rusting, creating rusty-brown water. Also, your hot water tank may be rusting. Water causing this type of problem is called corrosive. If you are having trouble and your neighbors are not, then your own pipes or water heater probably are rusting. Letting the water run a while will often clear the water (save the rusty water for plants). When your plumbing is rusting, lead and copper may be getting into your drinking water as well. This is important, so call your local water supplier to discuss this. To avoid problems with lead and copper, all water suppliers by law have to make sure that drinking water is not corrosive.

Q: Is it okay to use hot water from the tap to make baby formula?

A: No. Hot water may contain impurities that come from the hot water heater and plumbing in your house. To avoid this, use cold water and let the water run for a couple of minutes before you use it if that tap has not been used for a while, overnight, or all day. You can then heat this water in the microwave or on the stove. Catching the water you flush out of the tap in a container and saving it for plant watering is a good conservation measure.


Q: How should I fill my fish aquarium?

A: First, allow at least 1 gallon (4 liters) of water to run from the tap before using the water to fill the aquarium. This will flush any copper or zinc from copper or galvanized piping in your home; tropical fish are very sensitive to small amounts of copper or zinc in their water. Saving this water for other purposes such as plant watering is a good conservation measure. With a plate in one hand, pour water over the plate into the aquarium, allowing the water to drop about 1 foot (30 centimeters) before hitting the plate. This will add air (oxygen) to the water. Let the water sit in the aquarium for an hour or two until it reaches room temperature. Consult your local pet store to learn how to test for and remove any disinfectant in the water. Remove the disinfectant from the water in the aquarium before adding the fish.

How does lead get into the drinking water?

Not all drinking water contains lead. When household plumbing contains lead solder, and the water is in contact with the solder for long periods like overnight), their may be some lead that does dissolve and enter the water. This is also a function of the corrosivity of the water. Very hard water tends to from a scale on the walls of the pipes, and seals the solder. Lead solder has been outlawed since 1986.

Gas supersaturation
Tap water can be supersaturated with dissolved gases (especially nitrogen and carbon dioxide, but sometimes even oxygen), which when exposed to aquatic animals, can cause gas-bubble disease, a condition similar to the bends in divers. Supersaturation is generally problematic only in the winter when the water is especially cold and capable of holding even more gas. This condition is exacerbated when incoming water is pressurized from being pumped. The only treatment for supersaturation is time, which can be lessened with vigorous aeration to drive out the dissolved gasses (a process called off-gassing or degassing) and the application of heat. Aerating water to remove gas might seem counterintuitive, but remember that the water is supersaturated from being under pressure, and aeration at atmospheric pressure will bring the water back to equilibrium with normal air. Heating the water to room temperature will lower its ability to hold dissolved gases. Anyone who has allowed a tankfull of cold tap water to heat-up and observed the formation of tiny air bubbles on the glass is familiar with this process. Similarly, water heated for boiling first relinquishes its dissolved gas as tiny bubbles on the vessel walls before reaching a roiling boil.

Temperature and plumbing
Always use water from the cold tap and heat it (or allow it to warm to room temperature) in the aging tank. Water that passes through a hot water heater absorbs toxic heavy metals and minerals, which concentrate there like scale in a teapot. Also, hot water is more likely to leach toxins from metal pipes. Lead pipes are problematic at any temperature, for animals and humans, and should be replaced. Low-dose lead poisoning causes long-term neurologic problems. Water that sits in copper pipes overnight can absorb enough copper to cause acute copper toxicity and death in amphibians. Chronic copper exposure in some animals has been found to cause development of copper crystals in the liver. Old copper pipes, which might form an oxidized scale on the inside, seem less likely to leach than new ones. Running the water for several minutes before use to flush the system is a temporary partial fix. Using plastic (PVC or CPVC) pipes eliminates the problem of leached heavy metals and is ideal for cold water applications, but running hot water through them might cause the leaching of toxic vinyl chlorides. CPVC is more heat-resistant than PVC; flexible PVC (rubber hose) is worst.